Specialists worked for four months to individually clean each frame of the 1968 surreal tale by hand, the Beatles' holding company Apple Corps Ltd. said Tuesday.

The specialists chose not to use automated software because of the delicate nature of the hand-drawn artwork, the company added.

The colorful movie, a fantasy that features cartoon versions of the Beatles and images from some of their psychedelic songs, is currently out of print. It features some of the band's greatest hits including "Lucy in the Sky With Diamonds," `'Eleanor Rigby" and "When I'm Sixty-Four."

"As a fan of animation and as a film-maker, I tip my hat to the artists of `Yellow Submarine', whose revolutionary work helped pave the way for the fantastically diverse world of animation that we all enjoy today," said Pixar studios chief John Lasseter in the sleeve notes for the re-release.

The DVD will be released on May 28, and the film's soundtrack album will be reissued on CD on the same day.